1. Field of the Invention
This invention relates to a new reflective binary encoder for vector quantization. More particularly, the present invention relates to a vector quantization encoder and to a novel code book tree for use with vector quantization encoders to provide a non-uniform binary tree code book.
2. Description of the Prior Art
Vector quantizers are known and are described generally in the publications: "An Algorithm for Vector Quantizer Design" by Y. Linde, A. Buzo and R. Gray in IEEE Trans. on communications, Vol. Com-28, No. 1, Jan. 1980 and in "Vector Quantization in Speech Coding" by J. Makhoul, S. Roucos and H. Gish in Proceedings of the IEEE, Vol. 73, No. 11, Nov. 1985.
In my U.S. Pat. No. 4,727,354, there is disclosed a full search encoder for searching a random memory array but does not teach or suggest a reflective binary encoder or a non-uniform binary code tree book.
The article by Linde, Buzo and Gray, mentioned above, discloses an algorithm for designing a full search code book which has no code book tree structure to enhance search speed. This algorithm is widely known as the LBG algorithm.
The article by Makhoul, et al, mentioned above, discloses an algorithm for searching code books with embedded tree structures. A uniform and a non-uniform binary tree structure is disclosed.
It would be desirable to provide a new and improved encoder for vector quantization and associated therewith an improved non-uniform binary tree structure which enables faster encoding than the above-mentioned prior art structures.